Laser etching system and method

Abstract

The present disclosure provides laser etching systems and methods for etching a bottle. An example laser etching system includes a laser light source for generating a laser beam; a guide system for guiding the laser beam emitted by the laser light source. The guide system includes a 3D galvanometer system for adjusting the position of a focus of the laser beam. The laser etching system further includes a holding system for holding the bottle in a fixed position during laser etching and releasing the bottle after laser etching. The laser etching system further includes a control system used for generating a set of control signals according to a 3D model of the bottle. The control signals are used to control the guide system to dynamically adjust the position of the focus, such that the focus of the laser beam is located at predetermined positions of the surface of the bottle.

Description

LASER ETCHING SYSTEM AND METHODCROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of Chinese Patent Application No. 2023224783826, filed with the China National Intellectual Property Administration (CNIPA) on September 12, 2023, the disclosure of which is incorporated herein in its entirety.TECHNICAL FIELD

[0002] The present disclosure relates to laser etching or laser marking, in particular relates to a laser etching system or a laser marking system, and more particularly relates to a laser etching system or a laser marking system for etching or marking a bottle such as a beverage bottle.BACKGROUND

[0003] Laser etching or laser marking is a technique that uses a high-energy pulsed laser beam to irradiate a surface of an object with focused laser light to form an etched mark. The use of laser etching may cause a surface layer material to vaporize or undergo a color-changing chemical reaction; fine grooves having both micron-scale widths and depths are etched on the object surface, so as to form, for example, text, symbols, logos or images which are displayed on the surface of a component or product.

[0004] In the field of package manufacturing, laser etching is increasingly widely used for marking the surfaces of package products. Regarding conventional laser etching systems, during laser etching, an etching laser can only be controlled through an X-axis and a Y-axis that is orthogonal to the X-axis. However, when using this type of laser etching system to mark a package product, a relatively complicated surface shape of the package product itself is such that the focus of the etching laser is unable to always be located at the desired etching position, thereby affecting absorption of etching laser energy. If, for example, an image to be etched on a cylindrical package is wider in a direction perpendicular to a longitudinal direction thereof, then during the etchingprocess of this image, the focus of the etching laser does not always fall on the surface of the package product, and if the position of the focus extends beyond an acceptable tolerance range, then the etching effect will not be ideal.

[0005] To mitigate this problem, in the prior art, a method has been known to enable the focus of the etching laser to always be located on the surface to be etched directly facing the etching laser, for example by means of rotating the package product, thereby improving the etching effect of the laser etching. However, in the etching process, rotating a package product in coordination with the etching laser has high requirements for precision control of rotation of a rotation apparatus itself and precision control of the position of the package product relative to the focus of the etching laser. FIGS. 1A and IB respectively show an etched image divided into two visually separate portions formed by the methods according to this type of prior art, wherein a package product is rotated and the two portions are individually etched, and then joined to obtain an integral etched image. It can be seen from FIGS. 1 A and IB that these two separate portions of the image are not at the same height or are separated by a large gap, and thus break the integrity or coherence of the image. Hence such etching method is still unable to achieve a satisfactory etching effect.

[0006] In addition, a package product sometimes has unique shapes and structures, such as a ribbed part, an annular part or a planar part, etc., as shown in FIG. 2. When etching the surface in different regions of such a package product, if the focus extends beyond an acceptable tolerance range, then the design room may be severely limited.SUMMARY OF THE DISCLOSURE

[0007] The present disclosure provides techniques related to laser etching a package product, particularly a bottle, without rotating the package product, and with ability to adjust the focus of the etching laser to adapt to the shape of the bottle body of the bottle, thereby achieving a clear etched image in a larger etching range.

[0008] According to some embodiments of the present disclosure, a laser etching system is provided. The laser etching system includes: a laser light source operable and configured to generate and emit an etching laser beam; a guide system operable and configured to guide the etching laser beam emitted by the laser light source, the guide system including a three-dimensional (3D) galvanometer system, and the 3D galvanometer system being used for adjusting the position of a focus of the etching laser beam; a holding system operable and configured to obtain a bottle before laser etching begins, hold the beverage bottle in position during laser etching, and release the bottle after laser etching; and a control system operable and configured to generate a set of control signals according to a 3D model of the bottle, so as to control the guide system, such that the focus of the etching laser beam is dynamically adjusted and located at predetermined positions of a to-be-formed pattern on a surface of the bottle to etch the bottle and form the pattern. In some embodiments, the bottle has a curved surface around a longitudinal axis of the bottle, and the 3D galvanometer system is configured to adjust the focus in a focus range along an incident direction of the laser beam relative to the bottle.

[0009] According to one aspect of the present disclosure, the laser etching system is used for laser etching a bottle body of a beverage bottle. The beverage bottle may be a plastic bottle, a glass bottle, a metal bottle, a drink can, etc. The plastic bottle may be a PET bottle.

[0010] According to one aspect of the present disclosure, the laser light source may be a UV laser, a fiber laser, a CO2 laser or a picosecond laser.

[0011] According to one aspect of the present disclosure, the 3D galvanometer system includes: an X-axis galvanometer scanner and a Y-axis galvanometer scanner, the X-axis galvanometer scanner and the Y-axis galvanometer scanner being used for adjusting an optical path of the laser beam emitted by the laser light source; and a Z-axis adjustment system, which is used for adjusting a focus (i.e., a focal length) of the laser beam along the Z-axis.

[0012] According to one aspect of the present disclosure, when a diameter of the bottle body of the beverage bottle is 60 mm, an etching width of a clear etched design or pattern produced on the bottle body of the beverage bottle by the laser etching system according to the present disclosure is in a range of 45 mm to 50 mm.

[0013] According to one aspect of the present disclosure, when the diameter of the bottle body of the beverage bottle is 60 mm, a focus range of the laser etching system along an incident direction of the laser beam relative to the bottle according to the present disclosure on the bottle body of the beverage bottle is ±4.0 mm to ±4.9 mm.

[0014] By using the laser etching system provided by the present disclosure, the focus of an etching laser can be adjusted to adapt to a bottle body shape of a beverage bottle, such that the maximum etching width of a clear etched design produced thereby on the bottle body is increased by 40%, the focus tolerance is increased by 40%, and it is possible to obtain the outward appearance of the beverage bottle as envisioned.BRIEF DESCRIPTION OF DRAWINGS

[0015] The present disclosure is described in detail below with reference to the accompanying drawings. In the drawings:

[0016] FIGS. 1A and IB respectively show examples of integral etched images obtained by performing joined laser etching on a bottle body of a rotating beverage bottle using laser etching according to the prior art.

[0017] FIG. 2 shows an example beverage bottle with a bottle body that has a unique shape and uneven surface.

[0018] FIGS. 3A and 3B respectively show etched images at different contrasts using laser etching according to the prior art.

[0019] FIG. 4 shows examples of etched images formed on a rotating beverage bottle with different etching speeds using laser etching according to the prior art.

[0020] FIG. 5 is a schematic drawing illustrating an example focus of an etching laser.

[0021] FIG. 6 shows a schematic diagram illustrating an example laser etching system, according to various embodiments of the present disclosure.

[0022] FIG. 7A is a schematic drawing illustrating a cross section of a bottle body.

[0023] FIG. 7B is a schematic drawing illustrating a focus range of the laser beam etching a curved surface of a bottle body.

[0024] FIG. 8 shows example etched images formed with different etching widths using laser etching according to the prior art.

[0025] FIGS. 9A and 9B respectively show an etched image formed using laser etching according to the prior art and an etched image formed using laser etching according to the present disclosure.

[0026] FIG. 10 is a block diagram illustrating an example method for laser etching a bottle, according to various embodiments of the present disclosure.DETAILED DESCRIPTION

[0027] Certain exemplary embodiments are only simply described below. As a person skilled in the art may recognize, the described embodiments may be modified in various ways without departing from the spirit or scope of the present disclosure. Therefore, the accompanying drawings and description are essentially considered exemplary and non-limiting.

[0028] In the description of the present disclosure, it must be understood that orientations or positional relationships, indicated by terms such as "central", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "anticlockwise", etc., are based on the orientations or positional relationships shown in the drawings, and are only intended for conveniently describing the present disclosure and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be understood as a limitation of the present disclosure. In addition, the terms "first" and "second" are only used for descriptive purposes, and should not be understood as indicating or implying relative importance or implicitly designating a quantity to the technical feature referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly comprise one or more of said features. In the description of the present disclosure, the meaning of "multiple" is two or more than two, unless specifically defined otherwise explicitly.

[0029] In the description of the present disclosure, it must be explained that unless explicitly specified and defined otherwise, the terms "mount", "mutually connect" and "connect" should be understood in a broad sense, for example, may be fixedly connected, or may be detachably connected, or integrally connected; may be mechanically connected, or may be electricallyconnected, or may be mutually communicating; may be directly mutually connected, or may be indirectly mutually connected by means of an intermediate medium, or may be a connection inside two elements or a mutually acting relationship of two elements. For a person skilled in the art, the specific meanings of the above terms in the present disclosure may be understood according to the specific situation.

[0030] Embodiments of the present disclosure are described below in conjunction with the drawings; it should be understood that the embodiments described here are merely intended to illustrate and describe the present disclosure, not to limit the present disclosure.

[0031] In a laser etching process, several factors affect the image quality of laser etching; the factors include, but are not limited to, one or more of the following:

[0032] Contrast: to increase visibility, a greater contrast is needed between a material color and an etching color. FIGS. 3A and 3B respectively show etched images at higher and lower contrasts; it can be seen from these drawings that the colors of the etched image with the higher contrast are deeper and the image is clear. For a laser etching system, the contrast may be increased by using a higher etching laser energy. In addition, a higher energy may be obtained by increasing the power of the laser light source.

[0033] Etching speed: the speed at which the etching laser moves relative to the to-be-etched surface affects the etching process. Faster laser movement reduces the etching time, but reduces the absorption of etching energy with the result that the contrast / resolution of the image is lower. FIG. 4 shows, from top to bottom, etched images where the etching speed has gradually increased from 500 mm / s to 2000 mm / s. It can be seen therefrom that as the etching speed incrementally increases, the contrast of the etched image incrementally decreases, with the result that the resolution of the etched image incrementally decreases; the etched image when the etching speed is lowest is the clearest. Therefore, an etching objective is to increase etching speed while maintaining the same level of contrast.

[0034] Focus position: FIG. 5 shows a schematic drawing of a focus position of an etching laser. In a focusing process of the etching laser, the etching laser beam passing through a lens converges conically; the focus is located at the position of the tip of this cone shape, that is, where the highest amount of energy converges. During etching, the desired position of the focus of the etching laseris always located on a surface of an object being etched. For a typical laser etching system, if the distance between the surface of the object to be etched and the position of the focus is within a range of about ±1.5 mm, then the etching quality of the laser etching system is still considered acceptable.

[0035] FIG. 6 shows a schematic drawing of a laser etching system 100 according to the present disclosure. The laser etching system 100 is used for laser etching a bottle body of a bottle 200 (e.g., a beverage bottle), and includes: a laser light source 110, a guide system 120, a holding system 130, and a control system 140.

[0036] The laser light source 110 is used for generating and emitting a laser beam 112, and the power of the laser light source determines the energy of the etching laser beam that may be generated thereby. The laser light source 110 used in the present disclosure, for example, may include a UV laser, a fiber laser, a CO2 laser, a picosecond laser, etc.

[0037] The guide system 120 is used for guiding the etching laser beam emitted by the laser light source 110, and includes a 3D galvanometer system 121. The 3D galvanometer system 121 is operable and configured to dynamically adjust the position of a focus of the etching laser beam to adapt to the shape of the bottle 200 to be etched. In some embodiments, the 3D galvanometer system 121 includes one or more 3D galvanometers. Besides controlling an optical path of the etching laser beam at an X-axis and a Y-axis that is perpendicular to the X-axis, the 3D galvanometer system 121 further includes a component for controlling the optical path in a Z-axis direction, i.e., a Z-axis adjustment system 122 for adjusting a focus of the laser beam. Specifically, this is realized by arranging a Z-axis lens (or a group of Z-axis lenses) 122a on the Z-axis for dynamically adjusting the focus of the etching laser beam; this Z-axis lens (or a group of Z-axis lenses) 122a performs a reciprocating linear motion along the optical path in the Z-axis direction to compensate for a focusing error in real time. This dynamic focusing can compensate for any curvature or irregularities in the surface of the bottle 200 to achieve consistent etching quality. The 3D galvanometer system 121 according to the present disclosure may be respectively provided with an X-axis galvanometer scanner 123 and a Y-axis galvanometer scanner 124 on the X-axis and Y-axis; the X-axis galvanometer scanner 123 and the Y-axis galvanometer scanner 124 are used for adjusting the optical path of the etching laser beam.

[0038] In some embodiments, the X-axis galvanometer scanner 123 includes one or more movable or rotatable galvanometer mirrors 123a and a galvanometer motor 123b. Similarly, the Y-axis galvanometer scanner 124 includes one or more movable or rotatable galvanometer mirrors 124a and a galvanometer motor 124b. The galvanometer mirrors 123a and 124a are respectively driven by the galvanometer motors 123b and 124b to move or rotate in response to electric signals (i.e., the control signals) to reflect and precisely control the direction of the laser beam. The Z-axis adjustment system 122 further includes one or more lenses 122a arranged in the Z-axis direction and a lens motor 122b configured to control the one or more lenses 122a to adjust the focus of the laser beam in the Z-axis direction. In some embodiments, the lens motor 122b can control the one or more Z-axis lenses to perform a reciprocating linear motion in the Z-axis direction. In some embodiments, the Z-axis direction is the incident direction of the laser beam relative to the bottle 200.

[0039] The control system 140 can include an association module 141 and a driving module 142. The association module 141 is operable and configured to obtain a 3D model of the bottle 200, and generate a set of control signals for the guide system 120, on the basis of the 3D model, to control the guide system 120, such that the focus of the etching laser beam is adjusted to be located at predetermined positions of a desired pattern or design on the bottle body of the bottle 200 to etch the bottle body and form the pattern of design. The control signals determine the location (e.g., [X, Y, Z] coordinate positions) where the etching laser beam needs to focus and etch. The driving module 142 is operable and configured to drive the X-axis galvanometer scanner 123 (e.g., the galvanometer motor 123b), the Y-axis galvanometer scanner 124 (e.g., galvanometer motor 124b), and the Z-axis adjustment system (e g., the lens motor 122b), on the basis of the control signals, such that the etching laser beam, after emission from the laser light source 110, respectively undergoes dynamic focusing on the Z-axis, and reflection twice on the X-axis and Y- axis, before reaching a region to be etched on the bottle body of the bottle 200. Preferably, via dynamic control by the control system 140, the focus position of the etching laser beam is controlled to be located at the to-be-etched region on the bottle body of the bottle 200 within a focus range along an incident direction of the laser beam relative to the bottle 200.

[0040] In some embodiments, the control system 140 may include a computing system or computing device 143. The association module 141 and driving module 142 may each be a device(e.g., a mechanical or electrical device) coupled to and controlled by the computing system 143, or alternatively a software program implemented on the computing device 143 of the control system 140. In some embodiments, the association module 141 may scan the bottle 200 to obtain a set of position coordinates (e.g., [X, Y, Z] coordinates) defining a surface of the bottle 200. The association module 141 may further determine the position coordinates (e.g., [X, Y, Z] coordinates) of a desired pattern or design to be formed on the surface of the bottle. These predetermined positions are where the focus of the laser beam is controlled to be located on during etching. In some embodiments, the association module 141 may further calculate an etching path (e.g., moving a path of the focus of the laser beam) on the surface of the bottle 200. The etching path may contain a set of pre-determined position coordinates (e.g., [X, Y, Z] coordinates) for the focus to move on the surface. The pre-determined position coordinates of the etching path may vary in the Z-axis direction due to the curvature of the surface. The association module 141 may generate a set of control signals and send the control signals to the driving module 142. When the incident direction of the laser beam to the bottle 200 is along the Z-direction, the Z-axis adjustment system 122 may be controlled to adjust the focus of the laser beam along the Z-direction, according to the control signals including the pre-determined position coordinates of the etching path, so that the focus of the laser beam can be precisely and accurately located on the predetermined positions of the desired pattern.

[0041] According to an embodiment of the present disclosure, the holding system 130 is operable and configured to hold the bottle 200 before laser etching, keep the bottle 200 fixed during laser etching to ensure the bottle 200 is etched precisely and accurately, and release the bottle 200 after laser etching. In some embodiments, the holding system may include a robotic arm programmed to pick up the bottle 200, securely hold it in place during the laser etching process, and then release it once the process is complete. The robotic arm can be equipped with various end effectors (e.g., grippers) that are designed to handle bottles of different shapes and sizes. Other examples of the holding system include mechanical clamps, fixtures or jigs, vacuum suction cups, etc.

[0042] According to an embodiment of the present disclosure, the bottle 200 is a PET bottle or a drink can. Other bottles made of plastic, metal, or other etchable materials are also within the scope of the present disclosure.

[0043] FIG. 7A is a schematic drawing of a cross section of a bottle body of a bottle, according to an embodiment of the present disclosure. In the illustrated example, when a bottle with a bottle body diameter of 60 mm is laser etched, based on a circumference calculation formula:C = 7td (1) the circumference C of the bottle body of this beverage bottle is calculated to be 188.4 mm. When a conventional laser etching system according to the prior art is used, an etching width W achieved thereby is typically in a range of 25 mm to 30 mm.

[0044] Based on an etching angle calculation formula a = W / C * 360° (2) the upper and lower limit values of an actual etching angle that is achieved are calculated respectively: al = Wl / C * 360° = 25 mm / 188.4 mm * 360° = 48°, and a2 = W2 / C * 360° = 30 mm / 188.4 mm * 360° = 57°.

[0045] Additionally, according to an etching height calculation formulaH = d / 2 - cos(a / 2) * d / 2 (3) the upper and lower limit values of an effective etching height may be obtained through calculation, and are respectively:Hl = d / 2 - cos(al / 2) * d / 2 = cos(48° / 2)*60 mm / 2 = 2.6 mm, andH2 = d / 2 - cos(a2 / 2) * d / 2 = cos(57° / 2)*60 mm / 2 = 3.6 mm.

[0046] Thus, a focus range (±H / 2) of an etching laser in a laser etching system according to the prior art is calculated to be ±1.3 mm to ±1.8 mm; this focus range specifically depends on a balance between etching quality and etching speed. For example, if better quality is more important, whereas etching speed is not as important, then etching in a "focus ±1.3 mm" range may be selected.

[0047] As shown in FIG. 7B, when a laser beam is used to etch a curved surface of a bottle 200, the incident direction of the laser beam is the Z-axis direction, perpendicular to the surface of thebottle 200. For example, the laser beam moves in the Y-axis direction (or a X-Y plane) following an etching path including a start position 701, along positions 702, 703, 704, to an end position 705 to form a pattern on a curved region of the bottle. Each of the positions is represented by a set of [X, Y, Z] coordinates, and the coordinates of the positions vary along the Z-axis direction. For example, the Z-coordinate of the start position 701 is lower relative to the Z-coordinate of positions 702 and 703. The focus of the laser beam on the surface may be adjusted by the Z-axis adjustment system 122 to change and adapt to the curvature of the curved region within the focus range (H) along the Z-axis direction, so that the focus of the laser beam can be precisely located on the positions 701-705 when the laser beam moves from the start position 701 to the end position 705. The incident direction of the laser beam may remain in the Z-axis direction during etching.

[0048] As shown in FIG. 8, a laser etching system according to the prior art is generally able to achieve clear etching at an etching width W of between about 25 mm and 30 mm. Viewing FIG. 8 from top to bottom, as the etching width W reaches and exceeds 30 mm, for example when 33 mm, edges in the width direction W of the etched image become increasingly blurry or vague, and such a deficient mark affects the appearance of the product.

[0049] In comparison, when the laser etching system according to the present disclosure is used to etch the bottle body of the bottle, because the focus range in the Z-axis direction relative to the surface of the bottle can be adjusted in a broader range (i.e., ±4.0 mm to ±4.9 mm), the etching width W may be increased to 45 mm to 50 mm. Comparing FIGS. 9A and 9B, the etching width of the etched image achieved by a laser etching system according to the prior art is 28 mm, which is a smaller etching dimension, whereas the etching width W of the etched image achieved by the laser etching system according to the present disclosure can be 50 mm, almost doubling the etching dimension. Using the same calculation method and formulas (l)-(3) as above, the focus range of laser etching on the bottle body of the bottle according to the present disclosure also increases to ±4.0 mm to ±4.9 mm.

[0050] Therefore, compared to the laser etching system according to the prior art, beneficial technical effects achieved by using the laser etching system according to the present disclosure include:1. Increasing the etching width of the etched image by 40%.. Increasing focus tolerance by 40%.3. With a desired etching effect being achieved, the etching speed being affected to a certain degree but still within an acceptable range.

[0051] FIG. 10 illustrates an example method 1000 of etching a bottle performed by a laser etching system according to the present disclosure. In the illustrated example, method 1000 includes process blocks 1010-1050. At 1010, a to-be-etched bottle is identified and held, by a holding system of the laser etching system, in a fixed position. The holding system securely holds the bottle in place. In some embodiments, the bottle or a to-be-etched region of the bottle has a curvature or curved surface around a longitudinal or extending direction of the bottle.

[0052] At 1020, control signals are generated by a control system of the laser etching system. In some embodiments, a 3D model of the bottle is obtained by an association module of the control system. The 3D model includes all necessary surface contours and dimensions of the bottle, the to-be-etched region, and a desired or to-be-formed pattern. A set of control signals is generated, by the association module, based on the control signals. The control signals include coordinates [X, Y, Z positions] of the to-be-etched region and the desired pattern and focusing instructions required for the laser beam to etch the surface of the bottle and form the desired pattern with the to-be-etched region of the bottle. The control signals may also define the parameters for the etching process, such as laser power, speed, and depth of etching, depending on the material and design requirements.

[0053] At 1030, a laser light source of the laser etching system is activated, and a laser beam is generated and emitted by the laser light source. The laser beam is directed towards the to-be-etched area of the surface of the bottle by a guiding system of the laser etching system. An optical path of the laser beam along the X-axis and Y-axis is adjusted by a 3D galvanometer system of the guiding system. In some embodiments, an X-axis galvanometer scanner and a Y-axis galvanometer scanner are employed by the 3D galvanometer system to adjust the path of the laser beam.

[0054] At 1040, a focus of the laser beam is adjusted, by the guiding system, during the etching process to adapt to the dimensional profile or curvature of the bottle. In some embodiments, the focus of the laser beam is adjusted by using a Z-axis adjustment system including a Z-axis lens (ora group of Z-axis lenses) within the 3D galvanometer system to compensate for any curvature or irregularities on the surface of the bottle. A focus range of the focus of the laser beam, along the Z-axis direction (e.g., the incident direction of the laser beam) relative to the bottle, can be controlled in a range from ±4.0 mm to ±4.9. The control signals may be processed by a driving module of the control system to drive the X-axis galvanometer scanner, Y-axis galvanometer scanner, and Z-axis adjustment system to dynamically adjust the optical path of the laser beam and the position of the focus of the laser beam within the focus range and. The laser beam undergoes dynamic focusing on the Z-axis and reflections along the X-axis and Y-axis to locate the focus of the laser beam at predetermined positions of the desired pattern on a surface of the bottle. The desired pattern may span over a curved region of the surface of the bottle body around the central or longitudinal axis of the bottle. The desired pattern (e.g., logo, image, text, etc.) is formed on the bottle by laser etching with high precision and consistency.

[0055] At 1050, once the etching process is complete, the holding system is signaled by the control system to release the bottle.

[0056] Finally, it should be explained that the above embodiments of the present disclosure are for illustrative purposes only, and are not intended to limit the present disclosure. Although the present disclosure has been explained in detail with reference to the embodiments above, those skilled in the art should understand that they can still amend the technical solution recorded in each embodiment above or perform equivalent replacement of some of the technical features therein. Any amendments, equivalent substitutions or improvements etc., made within the spirit and principles of the present disclosure shall be included in the scope of protection thereof.

Claims

WHAT IS CLAIMED IS:

1. A laser etching system for etching a bottle, the laser etching system comprising: a laser source configured to generate and emit a laser beam; a holding system configured to obtain a bottle before etching and hold the bottle in a fixed position during etching; a control system configured to generate a set of control signals according to a three- dimensional (3D) model of the bottle, the control signals comprising predetermined positions of a to-be-formed pattern on a surface of the bottle; and a guide system comprising a 3D galvanometer system configured to dynamically adjust a focus of the laser beam according to the control signals and locate the focus of the laser beam at the predetermined positions to etch the surface and form the pattern.

2. The laser etching system of claim 1, wherein the surface of the bottle has a curvature around a longitudinal axis of the bottle, and the 3D galvanometer system is configured to adjust the focus of the laser beam in a focus range along an incident direction of the laser beam relative to the bottle.

3. The laser etching system of claim 1, wherein the 3D galvanometer system comprises: an X-axis galvanometer scanner, a Y-axis galvanometer scanner, and a Z-axis adjustment system, the X-axis galvanometer scanner and the Y-axis galvanometer scanner are configured to adjust an optical path of the laser beam, and the Z-axis adjustment system is configured to adjust a focus of the laser beam along the Z-axis.

4. The laser etching system of claim 3, wherein the Z-axis adjustment system comprises one or more Z-axis lenses configured to perform a reciprocating linear motion in the Z- axis direction to adjust the focus of the laser beam.

5. The laser etching system of claim 4, wherein when a diameter of the bottle is 60 mm, an etching width along a direction perpendicular to a longitudinal direction of the bottle is 45 mm to 50 mm.

6. The laser etching system of claim 4, wherein when a diameter of the bottle is 60 mm, the focus range is ±4.0 mm to ±4.9 mm.

7. The laser etching system of claim 1, wherein the holding system is further configured to: release the bottle after the etching is completed.

8. The laser etching system of claim 1, wherein the bottle is a beverage bottle.

9. The laser etching system of claim 8, wherein the bottle is a PET bottle or a drink can.

10. The laser etching system of claim 1, wherein the laser source is selected from a UV laser, a fiber laser, a CO2 laser, and a picosecond laser.

11. A method for etching a bottle, the method comprising: emitting, by a laser source, a laser beam; obtaining, by a holding system, a bottle and holding the bottle in a fixed position during etching; generating, by a control system, a set of control signals according to a three- dimensional (3D) model of the bottle, the control signals comprising predetermined positions of a to-be-formed pattern on a surface of the bottle, adjusting dynamically, by a 3D galvanometer system of a guide system, a focus of the laser beam according to the control signals and locating the focus of the laser beam at the predetermined positions to etch the surface and form the pattern.

12. The method of claim 11, wherein the surface of the bottle has a curvature around a longitudinal axis of the bottle, and the focus is adjusted by the 3D galvanometer system in a focus range along an incident direction of the laser beam relative to the bottle.

13. The method of claim 11, wherein adjusting the focus of the laser beam further comprises: adjusting an optical path of the laser beam by an X-axis galvanometer scanner and a Y-axis galvanometer scanner of the 3D galvanometer system; andadjusting a focus of the laser beam by a Z-axis adjustment system.

14. The method of claim 13, wherein adjusting the focus further comprises: perform a reciprocating linear motion in the Z-axis direction, by one or more Z- axis lenses of the Z-axis adjustment system.

15. The method of claim 14, wherein when a diameter of the bottle is 60 mm, an etching width along a direction perpendicular to a longitudinal direction of the bottle is 45 mm to 50 mm.

16. The method of claim 14, wherein when a diameter of the bottle is 60 mm, the focus range is ±4.0 mm to ±4.9 mm.

17. The method of claim 11, further comprising: releasing, by the holding system, the bottle after the etching is completed.

18. The method of claim 11, wherein the bottle is a beverage bottle.

19. The method of claim 18, wherein the bottle is a PET bottle or a drink can.

20. The method of claim 11, wherein the laser source is selected from a UV laser, a fiber laser, a CO2 laser, and a picosecond laser.

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